plot multiple equations in a for loop

Hi everyone. I am trying to plot multiple graph in Matlab. it seems that matlab over wrights the values in each loop so when i try to plot it doesn't give any results ....so how can i save the values for every loop to plot them ?? here is the code

tc=40;

te=15;

c1=137.402;

c2=4.60437;

c3=0.061652;

c4=-1.118157;

c5=-.001525;

c6=-.0109119;

c7=-.00040148;

c8=-.00026682;

c9=.000003873;

d1=1.00618;

d2=-.893222;

d3=-.01426;

d4=0.870024;

d5=-.0063397;

d6=.033889;

d7=-.00023875;

d8=-.00014746;

d9=.0000067962;

for ta=[20:5:50];

qe=c1+c2*te+c3*te^2+c4*tc+c5*tc^2+c6*te*tc+c7*te^2*tc+c8*te*tc^2+c9*te^2*tc^2;

p=d1+d2*te+d3*te^2+d4*tc+d5*tc^2+d6*te*tc+d7*te^2*tc+d8*te*tc^2+d9*te^2*tc^2;

a=1;

b=(0.54*10+6)/0.27;

c=10^2+(6*10)/0.27-qe/0.27;

te=(-b+sqrt(b^2-4*a*c))/(2*a);

qc=qe+p;

tc=(qc/9.6)+ta;

ta,qe,p,te,qc,tc,

end

plot(ta,qe,ta,p,ta,te,ta,qc,ta,tc)

Answer 1

[Michael Haderlein]

Please, use the {} Code button above the field you're writing your question to make the post be readable.

Also, you should learn about the array concept of Matlab. Your equations look kind of like scalar products, so most likely you can significantly shorten your code and avoid typos this way.

With respect to your question, in this case it's easier to loop with a counter from 1:7, create the respective ta from this and instead of writing data to scalars, save them in arrays. Such as

ta=zeros(1,7);
qe=zeros(1,7); 
for cnt=1:7
  ta(cnt)=cnt*5+15;
  qe(cnt)=...;
  ...
end
plot(ta,qe)

[majid eid]

 im a new matlab user ,here i tried to make the code readable

tc=40;

te=15;

c1=137.402;

c2=4.60437;

c3=0.061652;

c4=-1.118157;

c5=-.001525;

c6=-.0109119;

c7=-.00040148;

c8=-.00026682;

c9=.000003873;

d1=1.00618;

d2=-.893222;

d3=-.01426;

d4=0.870024;

d5=-.0063397;

d6=.033889;

d7=-.00023875;

d8=-.00014746;

d9=.0000067962;

for ta=[20:5:50];

qe=c1+c2*te+c3*te^2+c4*tc+c5*tc^2+c6*te*tc+c7*te^2*tc+c8*te*tc^2+c9*te^2*tc^2;

p=d1+d2*te+d3*te^2+d4*tc+d5*tc^2+d6*te*tc+d7*te^2*tc+d8*te*tc^2+d9*te^2*tc^2;

a=1;

b=(0.54*10+6)/0.27;

c=10^2+(6*10)/0.27-qe/0.27;

te=(-b+sqrt(b^2-4*a*c))/(2*a);

qc=qe+p;

tc=(qc/9.6)+ta;

ta,qe,p,te,qc,tc,

end

plot(ta,qe,ta,p,ta,te,ta,qc,ta,tc)

[Michael Haderlein]

Better than before, but simply using the {} Code button right above the edit control would even increase readability.

Could my answer solve your problem? It does not seem as if you had inserted my suggestion in this code.

[majid eid]

yes thank you very much michael, it worked :)